Bore pumps



Sept 13, 1966 G. L. TOWNER 3,272,45

Borm PUMPS Filed oct. z2, 1964 United States Patent O 3,272,145 BOREPUMPS Gresley Lukin Towner, Tooloon, Charleville, Queensland, AustraliaFiled Oct. 22, 1964, Ser. No. 405,768 2 Claims. (Cl. 10S-224) Thisinvention relates to reciprocating bore pumps, whether driven by windpower or by la motor.

Bore pumps are generally operated by a long rod to the lower end ofwhich the pump plunger is attached, the rod being reciprocated by thepower source to drive the pump.

On the up-stroke the pump has to lift a column of water the depth of thebore with consequent stress on the rod and power source.

As -will be appreciated, this stress is periodic in nature and its onsetis sudden on each occurrence with consequent strain and danger ofbreakage of the parts. This effect is accentuated by lwater hammer inthe bore, caused mainly by resonance surges of pressure in the watercolumn.

As a result, bore pumps are subject to breakdown and need constantrepairs and inspections, which, particularly in remote bores, involveslarge expenditure.

An'object of this invention is to reduce the stresses above referred to,and therefore reduce breakdowns.

A further object is to obtain .a more even flow from the pump.

In order that the invention may be better understood, one particularembodiment will now be described by way of example with reference to thesingle figure of the drawings, which shows in section a bore pumpaccording to the invention.

In general the bore is defined by a bore casing 10, in which a pump rodof jointed form reciprocates to drive a pump plunger, generallyindicated at 11, up and down to lift the water in the casing on theup-stroke. Pumps of this general type are well-known.

In this embodiment of the inventi-on, the sections 12, 13, 14 of thepump rod are of special form to be described below, and are coupledbetween a reciprocating power source (not shown) and plunger 11.

Each section 12, 13 and 14 is formed of a hollow tube of high-strengthmaterial such as high-tensile steel or fibre-glass. A threaded socket 15is secured in the upper part of each section and an externally threadedplug 16 in the lower part of sections 12, 13, the lower part of section14 being open, the plugs 16 and sockets 15 being screwed together tojoin the sections, and a resilient washer 17 being provided to seal eachjoint.

Sockets 15 and plugs 16 are each provided with a t central aperture 18leading to the interior of the section.

The aperture 18 of socket 15 in the upper section 12 is closed by =anon-return air valve 19 having means at its upper end to attach it to acompressor or air pump.

With the pump rod jointed together, there will be a continuous air spacealong its length, open at the bottom of section 14, and sealed by valve19 at the top of section 12.

The lbottom of section 14 is attached by suitable means, shown as at-ubular member 20, to the pump plunger 11.

The member 20 serves to connect section 14 mechanically to plunger 11,while providing apertures 20A, through which the water pressure withinthe casing 10 has access to the lower open end of the section 14 andtherekfore to the total air-space within the series of sections 14, 13,12.

A reduced diameter part 21 of member 20 passes Patented Sept. 13, 1966ICC through an upper bucket washer 22, a spacer 23 and a lower bucketIwasher 24 and is secured by a nut 25 thereon.

The plunger 11 as is well-understood will allow water to pass thewashers 22, 24 on the down-stroke but not on the up-stroke. The airspace within the pump rod acts as a shock absorber, for sudden changesof water pressure whether caused by the reciprocation of plunger 11 orby water hammer.

In use, the plunger 11 or its pump rod is lowered down casing 10 and, asthe `water head increases, the air in the interior of the rod iscompressed, water therefore rising some distance into the air space. Asthe pressure of W-ater changes on reciprocation of plunger 11, thevolume of air changes inversely and pressure shocks are minimized.

The practical effect of this cushioning is to reduce stresses on theworking parts of the pump and prevent water hammer, so making for muchlonger life of the pump.

The narrower parts of the air space, such as the apertures 18 tend toslow down the movement of air or water within the pump rod and furtherresist sud-den changes of pressure.

In addition, it is found that with the air space the flow from the pumpis almost constant instead of being of intermittent or stop-start typeas in prior pumps.

After long use, the air is found to be gradually reduced by solution inthe water. The air-space may be re-charged by passing air from anair-pump or compressor through the non-return valve 19 into theair-space.

Similarly for deeper bores, it is an advantage to increase lthe pressureof air in the space, and this again may be achieved via valve 19.

For shallower bores, up to 40 `or 50 feet deep, it is possible to -makethe pump r-od of a single section of t-ubular form with a non-returnvalve equivalent to valve 19 at its upper end and apertures equivalentto apertures 20A in its lower side Walls. Such `a construction gives theadvantages of the arrangement illustrated with a much simpler andcheaper construction. The only effect not attained is the damping effectof the constructions 18 in the -air space, and such effect is of littleimportance for shallow bores.

It is comparatively simple to convert a standard bore arrangement toincorporate the invention. All that is needed is to remove the usualpump rod and substitute a hollow rod and apertured tubular member 20, oran equivalent hollow rod arrangement and a valve 19. The plunger 11,casing 10 and means (not shown) for reciprocating the rod may be ofprior known type.

It has been found that the effectiveness of the air-space appears to begreater -with the apertures 20A situated immediately above the plunger11, rather than at some distance from said plunger.

It is pointed out that the air chamber in deep well pumps, for which thepresent invention is particularly suitable, to be properly effective,must be pressurized and this pressurization must be available in situ.According t-o the present invention this is accomplished by (l)providing an air chamber extending to the surface `within the pump rod,and (2) locating the recharging valve at the accessible upper end of thechamber.

Various other modifications and changes may be made in the equipmentdescribed without departing from the invention as defined by the claims.

What I claim is:

1. A reciprocating bore pump having a casing, a pump plunger within saidcasing, a hollow pump rod for reciprocating said plunger, the interiorof said rod forming an air chamber open to the water pressureimmediately References Cited by the Examiner UNITED STATES PATENTS297,076 4/1884 Hardie 103-224 X 334,211 1/1886 Babcox 103-224 X 336,0392/1886 Darnell 103-224 X 2,594,833 4/ 1952 White 103-224 ROBERT M.WALKER, Primary Examiner.

1. A RECIPROCATING BORE PUMP HAVING A CASING, A PUMP PLUNGER WITHIN SAIDCASING, A HOLLOW PUMP ROD FOR RECIPROCATING SAID PLUNGER, THE INTERIOROF SAID ROD FORMING AN AIR CHAMBER OPEN TO THE WATER PRESSUREIMMEDIATELY ABOVE SAID PLUNGER AND EXTENDING CONTINUOUSLY TO THE SURFACEOF SAID BORE, A NON-RETURN AIR VALVE CLOSING THE UPPER END OF SAIDCHAMBER AND MEANS FOR ATTACHING A SOURCE OF COMPRESSED AIR TO SAID VALVETO RECHARGE SAID CHAMBER,